Percentage of performance obligation to be recognized as revenue.

No definition available.

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- Definition

Performance obligation expected to be recognized as revenue, year.

+ References

No definition available.

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- Definition

Revenue from contract with customer line items.

+ References

No definition available.

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- Definition

Amount of accumulated amortization of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, before accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Topic 606
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-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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- Definition

Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 12
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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

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- Definition

Year in which remaining performance obligation is expected to be recognized, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Revenue (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Revenue (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Revenue From Contract With Customer [Line Items]
Revenue, remaining performance obligation	$ 707,091
Percentage of performance obligation to be recognized as revenue	76.00%
Performance obligation, expected to be recognized as revenue year	2019
Remaining performance obligation, expected timing of satisfaction, year	2020
Revenue, description of timing	one year or less
Contract revenues	$ 620,795	$ 592,159	$ 637,468
Amortization on pre-construction costs	15,411
Long-lived assets, net book value	30,601	47,563
Other Current and Noncurrent Assets [Member]
Revenue From Contract With Customer [Line Items]
Costs to fulfill contracts with customers recognized as an asset	13,129			$ 6,754
Foreign [Member]
Revenue From Contract With Customer [Line Items]
Contract revenues	$ 14,088	$ 42,306	$ 59,413
Dredging [Member] \| Sales [Member] \| Federal Government Agencies [Member] \| Customer Concentration Risk [Member]
Revenue From Contract With Customer [Line Items]
Concentration risk percentage	75.50%	63.40%	64.30%
Dredging [Member] \| Accounts Receivable [Member] \| Federal Government Agencies [Member] \| Customer Concentration Risk [Member]
Revenue From Contract With Customer [Line Items]
Concentration risk percentage	65.30%	42.80%
Dredging [Member] \| Foreign [Member]
Revenue From Contract With Customer [Line Items]
Contract revenues	$ 14,088	$ 42,306	$ 59,413
Dredging [Member] \| Middle East [Member] \| Sales [Member] \| Geographic Concentration Risk [Member] \| Maximum [Member]
Revenue From Contract With Customer [Line Items]
Concentration risk percentage	10.00%	10.00%	10.00%
Dredging [Member] \| Middle East [Member] \| Accounts Receivable [Member] \| Geographic Concentration Risk [Member] \| Maximum [Member]
Revenue From Contract With Customer [Line Items]
Concentration risk percentage	10.00%